Anastomosis is a surgical term for describing the joining of two hollow bodies, particularly blood and lymphatic vessels. Anastomosis can be end-to-end, as when the ends of a severed or damaged vessel are rejoined, or end-to-side, as when an end of a vessel is joined to the side of another vessel or hollow structure. The primary method for surgically anastomosing vessel ends has been the circumferential suture, in which a suture is hand applied around the ends of the two vessels. Circumferential suturing is a time-consuming, exacting process. It is very important that the ends of the vessels be joined properly, as leakage or obstruction of the vessel lumen is possible, with potential serious effects on the patient's health. The physical manipulation of the vessel that is necessary for circumferential suturing can also result in damage to the vessel ends, with resulting degradation of the anastomosed vessel.
Various mechanical methods have been proposed for performing end-to-end anastomosis without circumferential suturing. One such anastomosis system and method is described in Poo et al. U.S. Pat. Nos. 8,348,128 and 8,777,084, which describes a circumferential anastomosis device. Anastomosis of vessels requires clamping the vessels during the anastomosis procedure. The inclusion of vessel clamps alongside anastomosis devices is limited by the space available in the surgical environment. In some forms of surgery, space for clamps and anastomosis devices is extremely limited.